SAM L11 Secure Pin Multiplexing
Secure Pin Multiplexing on Serial Communication (SERCOM) Overview
The Secure Pin Multiplexing feature can be used on dedicated SERCOM I/O pins to isolate a Secured communication with external devices from the Non-Secure application. This feature is automatically enabled as soon as the security attribution of the SERCOM is set to Secured using the Peripheral Access Controller (PAC) peripheral.
When this operation occurs:
- The Secured SERCOM instances become mapped only on a specific set of I/O pins.
- All of the alternate I/O pins of the Secured SERCOM instance are kept in a Hi-Z configuration.
- The Peripheral Touch Controller (PTC) cannot enable PTC lines mapped to any of the Secured SERCOM instance I/O pins.
- The Configurable Custom Logic (CCL) I/Os mapped to the Secured SERCOM instance I/O pins are set to "0".
Table 1
Once this feature is enabled (SERCOM1 configured as a Secured peripheral), only the SERCOM1 pins from Table 1 become mapped. All of the alternate SERCOM1 pins are kept in a Hi-Z configuration and cannot be selected for that specific SERCOM.